cats

dono200sx · Nov 5th, 2002, 04:26 PM

How can I tell if my cat is bad? A while back my check engine light came one with a code for my rear o2 sensor. I just checked the sensor and it is still whole (not corroded) so I am assuming it is still good. I took the cat off and tried to look through it, and it is dang near impossible to see through it. Is that a sign of it being out?

If it is I'm gonna get a test pipe to put in its place until I can get the money to buy a Randon Technology cat. TIA!

phil_minchoff · Nov 5th, 2002, 11:10 PM

if you haven't noticed any changes in performance or running, i'd say let it go till you buy the new cat. that'll solve your problems and then some.

javierb14 · Nov 5th, 2002, 11:35 PM

u can tell if the rear o2 sensor is good/bad by checking the voltage with a voltmeter. how many miles on ur car.

dono200sx · Nov 6th, 2002, 09:55 PM

The only reason I am even worrying about the cat is b/c my rear o2 sensor is throwing up a code. The CEL came on only a month or two after I got the car, so I haven't noticed a difference in power. I reset the ECU, but that was to no avail. It came back on last night. I have 92k+ miles on her.

I'm thinking about temporarily putting in piping instead of a cat. Until I can save up the money for the Randon Tech. Would that just be a matter of tig welding some flanges onto some exhaust piping and bolting it on? I'm sure I'll have to have the shop create a spot on it for the sensor.

My only question about that is will that still trip the check engine light? I know it's illegal here to run w/o a cat, but it should only be on there long enough to receive the cat, so I'm not too worried about getting a ticket or anything.

javierb14 · Nov 6th, 2002, 10:12 PM

im running an open downpipe without a cat on my b14 with the JWT ecu. when i first turbo'd it, it threw a rear o2 code all the time......i guess it learned, since it doesnt do it anymore. ive been thinking about a o2 simulator. check it out
http://www.mkiv.com/techarticles/oxy...sor_simulator/

dono200sx · Nov 7th, 2002, 11:28 PM

Well hopefully my ECU will learn, b/c i'm sick of the CEL being on. Does anyone have a ballpark idea of how much i can expect the cost to be to have the pipe and o2 sensor installed?

Centurion · Nov 8th, 2002, 05:59 AM

You could always just ream out the cat, no need to make a test pipe.

myoung · Nov 8th, 2002, 11:36 AM

Quote:

Originally posted by javierb14
im running an open downpipe without a cat on my b14 with the JWT ecu. when i first turbo'd it, it threw a rear o2 code all the time......i guess it learned, since it doesnt do it anymore. ive been thinking about a o2 simulator. check it out
http://www.mkiv.com/techarticles/oxy...sor_simulator/

So the car is running again? If so, ever get any dyno runs?

This really isn't worth all this trouble.. Just install a Random or 98 ca model Nissan cat.. today's cats aren't big restrictive hogs like the old days... no reason to be a mass pollutor for a very very minimal gain.

dono200sx · Nov 9th, 2002, 08:57 PM

If I had any money I would throw on a Random Tech cat. I also don't see a point in polluting unnecessarily. If I did put on the test pipe it would only be for long enough to getthe money saved up for the new cat and for taking the car to the strip and trying to squeeze some more power out of the engine.

So who sells a random tech cat for cheap? I'm trying to get my dad to loan me the money for the cat, so maybe I'll be able to get it soon.

Nov 10th, 2002, 03:56 PM

I don't believe your cat is the problem. There would be a different ecu code if it was the cat that was messed up. You said that you can't see through it. You shouldn't be able to. The inside is made up of some clay like stuff. So not being able to see through it doesn't mean its clogged. If it was clogged you would smell a nasty sulfer smell every time you made to the high rpm. I'm betting its the o2. Try to test the o2 sensor with a votmeter and that will tell you whether or not the o2 sensor is bad.

javierb14 · Nov 11th, 2002, 11:45 PM

Quote:

So the car is running again? If so, ever get any dyno runs?

oh ya...now that its a lot cooler at night here in AZ its running great

, till the clutch slips. no, now dyno runs or 1/4 mile times....i still need a clutch disk. i have a JWT flywheel, stage 2 pressure plate, new throwout bearing, and OEM clutch disk. but i dont think the stock disk will last very long. im thinking about the ACT 4 puck or JWT stage 2 disk. u have the JWT disk right, how do u like it?

dono200sx · Nov 12th, 2002, 12:56 AM

What is the voltage supposed to read for the o2 sensor? Thanks for clarifying about the cat.